Pick wheel operated loom stop motion mechanism



June 10, 1952 Filed Aug. 4, 1950 L. H. ROCKWELL PICK WHEEL OPERATED LOOMSTOP MOTION MECHANISM 3 Sheets-Sheet 1 m Ian? v IN V EN TOR.

5 LUDLUM hf ROCKWELL 27 4M mm 0mm ATTOENEYS.

June 10, 1952 PICK Filed Aug. 4, 1950 L. H. ROCKWELL 99,584

WHEEL OPERATED LOOM STOP MOTION MECHANISM 3 Sheets-Sheet 2 FIG. 2

INVENTOR.

June 10, 1952 fiQc KwELL 2,599,584

PICK WHEEL OPERATED LOOM STOP MOTION MECHANISM Filed Aug. 4, 1950 5Sheets-Sheet 3 FIG. 7. A76. 6. 60 45 INVENTOR.

LUOL UM ROCKWELL,

Patented June 10, 1952 PICK WHEEL OPERATED LOOM STOP MOTION MECHANISMLudlum H. Rockwell, Bloomsburg, Pa. Application August 4, 1950, SerialNo. 177,654

4 Claims.

This invention relates to loom stop motion mechanisms and moreparticularly to a stop motion switch operated by a loom pick wheel tostop the loom whenever the pick wheel fails to make a full forward step.

It is among the objects of the invention to provide a stop motion switchmechanism for a loom which will immediately stop the motion of the loomwhenever the loom pick wheel and associated mechanism fail to complete afullforward rotational step, thus protecting the woven fabric againstirregularities occasioned by running two or more yarn threads in thesame space in the warp of the fabric, which mechanism can be easilyinstalled on an existing loom adjacent the loom pick wheel and operatedby movement of the pick wheel, which is ineffective to stop the loomexcept upon failure of the pick wheel to complete a forward rotationalstep, which is fully adjustable for accurate operation and toaccommodate the mechanism to various loomsand pick wheels, and which issimple and durable in construction, economical to manufacture, easy toin stall, and positive and effective in operation.

Other objects and advantages will become apparent from a considerationof the following description and the appended claims in conjunction withthe accompanying drawings wherein:

Figure 1 is an elevational view of a fragmentary portion of a loomshowing a loom pickwheel and a stop motion switch mechanism illustrativeof the invention operatively mounted on the loom adjacent the pick wheel7 j Figure 2 is a top plan view of the loom fragment and stop motionswitch mechanism illustrated inFigure 1, portions being broken away andshown in cross section;

Figure 3 is a side elevational view on an enlarged scale of the stopmotion switch mecha msm; l

Figure 4 is a top plan view of the stop motion switch mechanismillustrated in Figure 3;

Figure 5 is a cross sectional view on the line 5-5 of Figure 3;

Figure 6 is a cross sectional view on an enlarged scale on the line 6-6of Figure 3;

Figure 7 is a cross sectional view on the line 1-1 of Figure 3;

Figure 8 is a side elevational view of a modified form of stop motionswitch mechanism;

Figure 9 is a top plan view of the mechanism illustrated in Figure 8;and

Figure 10 is a side elevational view of a still further modified form ofstop motion switch mechanism. g r

With continued reference to the drawings, and particularly to Figures 1and 2, the fragmentary portion of the loom illustrated includes a loomframe I!) provided with suitable bearings, as indicated at II, for apick wheel and pick spool or cylinder shaft, a pick wheel l2 mounted onone end of the shaft at the outer side of the frame H], a handwheel l3mounted on the same end of the shaft and disposed outwardly of the pickwheel l2 for manually rotating the pick wheel and pick cylinder to takeup slack in the cloth or fabric on the loom, a pick wheel rotating arml4 pivotally mounted intermediate its length on the pick wheel shaft, alink l5 connected between one end of the arm [4 and the loom drivemechanism to impart angular, oscillating movement to the arm [4, a pawll6 pivotally mounted on the other end of the arm [4 and engageable withthe ratchet teeth I! on the periphery of the pick wheel to impart stepby step rotational movement to the pick wheel, and a locking pawl I 8pivotally mounted on the frame at a, location spaced from the pawl l6and engageable with the pick wheel ratchet teeth I! to hold the pickwheel against reverse rotational movements.

As long as the pick wheel operating mechanism is all in perfectoperating condition and there is no material wear or looseness, the pawlIE will advance the pick wheel a full step each time the arm l4 ismovedby the link l5 and the locking pawl I 8 will drop behind successiveratchet teeth permitting no back movement of the pick wheel. However, ifthe pawl l6 fails to advancethe pick wheel the full forward step, thelocking pawl l8 will not clear the ratchet tooth with which it isengaged and drop behind this ratchet tooth, thus permitting the pickwheel to turn back to its original position when the arm 14 is returnedin its oscillating movement. If theloom continues to operate under theseconditions, the shuttle will be passed a second time through the samespace in the warp, laying two yarn threads side by side in the samespace and producing an irregularity in the cloth. If the pick wheelshould repeatedly fail to advance, the shuttle will, of course, continueto lay yarn threads in. the same space since the warp does not advanceunless the pick wheel rotates. The passing of the shuttle repeatedlythrough the same space in the warp will necessitate shutting down theloom while the extra yarn threads are removed and may even then resultin an irregularity in the cloth and may even cause a serious jamming ofthe loom.

With the present invention in operation, if the open and the operationof the loom will not be interrupted. However, should the pick wheel movein a reverse direction when the pawl I6 returns, the adjacent ratchettooth will contact the extension 52 of the switch arm and move nectedeither directly or indirectly into the motor circuit for the loomdriving motor so that operation of the loom will be discontinuedimmediately upon closing of the stop motion switch.

After the loom has been stopped the loom operator will make thenecessary adjustments in the pick wheel rotating mechanism to render thepawl I6 effective to advance the pick wheel a full step each time themechanism operates. As soon as the ratchet tooth pressure on the switcharm extension 52 has thus been relieved the loom can be restarted andwill continue to operate until the pick wheel again fails to make acomplete forward rotational step.

The pivot screw 48 for the switch arm 41 is also electrically insulatedfrom the lever 34 and the switch arm itself is electrically insulatedfrom this lever to avoid the danger of any accidental short circuitbetween the switch arm 41 and the socket 44. As illustrated in Figure 6,a flat plate 54 of electrically insulative material is interposedbetween the socket 44 and the switch arm 41 and apertured to receive thepivot screw 48 and the socket stem 55. Sleeves 56 and 51 of electricallyinsulative material surround the screw 48 and stem 55 respectively inthe apertures provided therefor in the plate 35 and nuts 56 and 59 arethreaded on the screw 48 and the, stem 55 respectively at the side ofthe plate 35 remote from the insulating body 54. As the switch arm 41makes a ground contact with the pick wheel of the loom, the single wire45 is sufiicient to complete the switch circuit, this wire beingconnected to the socket 44 by the terminal 66.

In the modified arrangement illustrated in Figures 8 and 9, the bracket20, described above, is replaced by an elongated bar 6| which is securedat some convenient location along its length to the frame of the loom ina manner to position the stop motion switch mechanism contiguous to theperiphery of the pick wheel of the loom.

A notch 62 is provided in the pick wheel adjacent of the bar 6|intermediate the length of the latter and a tongue or detent 63 issecured to the bar at one end of this notch for positioning the barrelative to the pick wheel of a loom.

Otherwise, the mechanism is substantially the same as that illustratedin Figures 1 to 7 inclusive and described above and includes the lever34 pivotally connected at one end to the bar 6| by a bolt or screw 26,the bolt 25 adjustably connecting the plate 35 to the free end of thelever 34 and extending through the slot 31 in the adjacent end of thebar 6|. The plate 35 carries the fixed contact socket 44 and fixedcontact 46 and the switch arm 41 pivotally connected to the plate by thepivot screw 48. The

plate 35 is provided with the detent and the switch arm 41 with theextension 52 engageable by a ratchettooth on the pick wheel to close theswitch in the above described manner.

In the further modified arrangement shown in Figure 10, the constructionis substantially the same as that illustrated in Figures 8 and 9 anddescribed above, except that the lever 34 is omitted, the detent 63 isadjustably connected to a bar 64, corresponding to the bar 61, and theplate, 35 is adjustably connected directly to the bar 64 ata locationspaced from the detent e3.

In this arrangement, the lever 64 will be pivotally mounted on asupporting structure, such as the loom frame so that the plate 35 canmove up and down as the pick wheel rotates. The detent 63 is providedwith an elongated, transversely extending slot 65 receiving the bolt orscrew 32 so that the detent can be adjusted longitudinally of the bar64. The lever 35 is provided with a longitudinally extending slot 66receiving the bolt 25' so that the plate can be adjusted bothlongitudinally and angularly of the bar 64. In this case, the bolt 25may be a simple bolt without the shoulder providing enlarged portion 39of the bolt 25. Otherwise, the operation of the form of the inventionshown in Figure 10lis the same as that described above in connectionwith Figuresl to 9 inclusive.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiments are, therefore, to be considered in all respects asillustrative and not restrictive,

the scope of the invention being indicated by the appended claims ratherthan by the foregoing description, and all changes which come within themeaning and range of equivalency of the claims are, therefore, intendedto be embraced therein.

What is claimed is:

1. In combination with a loom having a frame, a pick wheel journaled onsaid frame and provided with peripheral ratchet teeth, means engageablewith the pick wheel teeth for imparting step by step rotational movementto said pick wheel, means engageable with said pick wheel teeth as eachstep is completed to hold said pick wheel against return movement, pickwheel operated switch mechanism for stopping the loom motion uponfailure of said pick wheel to complete a full rotational step comprisinga bar pivotally mounted on the loom frame and disposed adjacent theperiphery of said pick wheel, a detent on said bar engaging said ratchetteeth and dropping into the spaces between adjacent teeth as said pickwheel rotates, a fixed contact carried by said bar adjacent said detent,a switch arm pivotally mounted on said bar and carrying a movablecontact complementary to said fixed contact, and a spring connectedbetween said bar and said switch arm resiliently urging said movablecontact away from said fixed contact, said arm including a portionextending along said detent and projecting from one side of the latterfor engagement by said ratchet teeth to move said movable contact intoengagement with said fixed contact upon reverse rotational movement ofsaid pick wheel.

2. In combination with a loom having a frame, a pick wheel journaled onsaid frame and provided with peripheral ratchet teeth, means engageablewith the pick wheel for imparting step by step rotational movement inone di-

